Toggle lever press



Oct. 16, 1945.

A SCHNEIDER ETAL .TOGGLE LEVER PRESS Filed April :5, 1958 s Sheets-Sheet 1 a I nrenfars Scfiaze zTal e page ZZeaean I owe? Oct. 16, 1945.

A. SCHNEIDER :rAL

'I'OGGLE LEVER PRESS Filed Apf'll 5, 1938 5 Sheets-Sheet 2 In van fats ACZOZ/ 502212 e z'd'ez' Ia/aZd' Wage Zfiaezni by @M Afiorney A. SCII-IINEIDERETAII. 2,387,041

Oct. 16; 1945.

' TOGGLE LEVER PRESS Filed April 5, 1938 5 Sheets-Sheet 3 I jfll efl fo /5 AdoZf Selene z'dez', 340a ZaZ Maya ZZea 627 a. Attorney Oct. 16, 1945. i A. SCHNEIDER ETAL' 1 TOGGLE LEVER PRESS,

Filed April 5, 1938 5 Shets-Shegt 4 Oct. 16, 1945. A. SCHNEIDER ETAL I 2,387,041

' TOGGLE LEVER PRESS Filed April 5, 1938 5 Sheets-Sheet 5 d" we,

Patented Oct. 16, 1945 2,387,041 I TOGGLE LEVER PRESS Adolf Schneider and Ewald Ungethuem, Karls- Property Custodian ruhe, Baden, Germany:

vested in the Alien Application April 5, 1938, Serial No. 200,282 A In Germany April 10, 1937 V der I4 by hydraulic pressure which is fed and 4 Claims.

invention relates to a toggle lever press.

It is an object of the invention to increase the speed and output of toggle lever presses, to simplify the construction and to reduce the manufacturlng cost of such presses.

Another object of the invention is to facilitate the operation of toggle lever presses.

Another object of the invention is to facilitate the ejecting operation.

Still another object is to provide a simple means for adjusting the end positions of the ram.

With these and further objects in view, we provide means for effecting the control of the press by hydraulic pressure. More particularly, we control the end positions of the ram, the press table,

the ejector and the main shaft by hydraulic pressure.

The invention will be better understood by reference to the following detailed description in connection with the accompanying drawings showing by way of example and diagrammatically an embodiment of our toggle lever press.

Fig. 1 is an elevation, partly in section, viewed in the direction of arrow A in Fig. 2 ofa toggle lever press having the invention applied thereto.

Fig. 2,is a side elevation, partly in section, of the press shown in Fig. 1.

Fig. 3 is an elevation of the same press viewed in the direction of the arrow B in Fig. 2.

Fig. 4 is a plan view of the press.

Fig, 5 is a section on'line C-D in Fig. 3.

Fig. 6 is a schematic diagram of the control system.

. Referring now to the drawings in greater detaiLVand first to Figs. 1 to 5, the press comprises a main frame II in which the press, table 22 is mounted for lateral sliding motion under action of a hydraulic system 23, 24, 46, as will be hereinafter described. A ram 9 is mounted to slide vertically in suitable guides of the main frame, under action of a toggle lever system 6, l, 8, I0, in the manner known per se.

The drive of the press will now be described. A pulley 2 fast on a shaft 2' is driven from' a motor I with pulley I, by a number of cone belts 3, and in turn drives, through coupling I 02, main shaft 33, a slipping clutch I05 and gear wheels I03, and I04, and shaft 4 and a gear wheel 5 on shaft 45. Mounted on a crank 45' of shaft 45 is a connectingrod 6 actingupon a toggle lever system comprising thrust rods I and 8, a stationary support or abutment I0 and a ram 9 upon which the pressure of said system is exerted. The support I0 bears against an adjustable wedge member II which in turn bears against the transverse or bridge portion of the main frame IOI. The wedge member II is mounted to be movable in a horizontal direction by a thrust rod I2 forming part of a piston I3 movable in a cylin- Lil controlled in the manner which will be hereinafter described, so as to control the vertical position of the support I0 which bears against the lower inclined face of said wedge member II.

The toggle joint support I0 is connected, through two tension rods I5, with a cross bar I6 which can be acted uponby hydraulic pressure in the cylinder 48, through a piston I1 and piston rod 49, thus urging the toggle joint support I 0 against the wedge face II and lockingthe wedge member in its adjusted position. The actual position of the adjustable wedge member II is shown by an indicator I8 consisting of an index 50 movable on a scale 5| and rotated, through a bevel gear 52 fast on the pointer shaft and a bevel gear 53 fast on the left hand end of shaft I9, from a rack 2I fast on the adjustable wedge member I I and engaging a toothed wheel 20 fast on theopposite end of shaft I9. In this manner, the lower and upper end positions of the ram 9 are controlled, locked and indicated.

The press table 22 can be horizontally moved by means of a hydraulic piston 23 movable in a cylinder 24 and secured to a thrust rod'46 connected with the plate 25. An ejector rod consisting of an upper part 26 and a lower part 21 extends through the 'plate'25 and the table 22. Connected to said lower portion 21 is a piston 28 movable in a hydraulic cylinder II'I under control ofthe pressure of a liquid admitted to either side of the cylinder II! by ducts and control valves, which will be hereinafter described. In order to ensure that the ejecting operation can take place only when the ejector member 26 is positioned accurately vertically above the member 21, partly toothed rods 29, 30 moved by a toothed wheel 34 on shaft 36, are provided to engage recesses 3| and 32 of the member 21 and the plate respectively when said parts are in the correct positions. The shaft is rotated by depression of the lever 31, pivoted at 38, through a rod IBIand a lever 54. The lever 31 is connected by shaft 38 with a valve controllin rod 39 controlling the piess liquid for a hydraulic system I I2, II 6 (Fig. 6) by which the coupling I02 is operated as will be hereinafter described.

Referring now to Fig. 6, there is shown a diagram of the hydraulic control system. Two gear pumps I06 and I01, connected through valve 91 and driven by an electromotor I08, through a coupling I09, supply oil or water under pressure from a storage tank IIO through pipe I00 into the Pipe system comprising the control valves, cylinders and pistons, while the excessive quantitles of oil are fed back into the storage tank IIO, through relief valves 98 and 99 and pipes I II and III The elements of the hydraulic pipe system are known per se and need not be described in detail here. Therefore, it will be suflisupplied to pipe ID while pipe I25 is opened to discharge pipe 93 and pip I40, to discharge pipe 95, whereupon piston I1 and support ID are dropped, freeing wedge H', and piston I3 is moved to the right to shift the wedge II in that direction, Fig. 6-. In reverse manner, when handle. 43 is moved inward beyond middle position,

H3, the piston H2 and shaft 33 will'bemoved j in right hand direction and shaft 33 will be coupled with the driving shaft 2, by engagement of the coupling I62 so that the togglelever system is operated. Again, when the pressure in pipe H3 exceeds the pressure in pipe H4, the piston H2 and shaft 33 will be moved in a left' hand-direction, releasing the coupling ")2; and theflange or collar 33 on shaft 33-will engage the stationary brakedisc-I 15, so that the press comes to astandstill. It will be understood that it is notnecessaryfor the main shaft 33 to pass through-thev cylinder Ht, but in practice the mechanicalconnection betw'eenpiston' H2 and andshar't 33 or coupling Hi2 and brake H5 respectively will be established i in the manner shown in Fig. 4; by means of atwin arrangement ofycylinders H6 operating on shaft 33by a cross bar I41. engaging a suitable annular groove in the shaft 33 or in a flange M8 on said shaft respectively. l

The operations of the press are controlled entirelyby hydraulic pressure by movement of lever 31 whichactuates rod 39:threug-h a rack and pinion connection at 39'. The rod 35 extends through a valve casing I60 and carries control pistons I2fl,-i2| and I22 and member I23, which are shownin full line in middle positions as maintained by a spring l38. The spring I38 is operative to restore the rod and the associated control pistons to the full line position shown from either of the dotted line positions shown, which are the positions occupied by the control pistons when the lever 31 is moved to upper and lower operating-positions. Spring pressed latchingmembers I33 and I34'are disposed forengagementwith the notch I37 in-member I23 in the respective actuated positions of the 'member I23 and rod-39; the latching'membersare adapted to bereleasedbyhydraulic pressure on'pistons l29-and I as, as willbe further-described, forallcwing spring I38 to restore the rod 39 to middle position. 1 I 'j' Piston 1251s essentially a sealing member. Piston I-2I alternately opens pipe I i4-to pressure from pipe Hid-when-lever 31 is depressed, and

pipe I58 to discharge pipe HI, when lever 31 is 5 raised; Piston I22 alternately opens pipe-L59 topressure from pipe I03, when lever 3'! is raised, andpipe I is to discharge pipe I I I through connecting pipe 534, when lever'3'I' is'depr'essed. It will be noted that pressure supply is continuous from. pipe Illfl to pipe 35 leading to valve I25, and that dischargepipes 95 and III, and '93-and 94, are similarly continuously open-through valve casing I60.

The adjustment of the press stroke by wedge H is controlled by valve=l25 by movement of handl 43. -'lhe valve includes a valve casing I24 within which the valve member I25 is slidable by handle 43. Inth'e middle position shown, pressureis admitted-from pipe 96 through passages in-the valve member and pipe I 40 to cylinder 48, where piston I7 is raised and the support I,0is likewise raised; through rods l', to position againstwedge H. \Vhen handle 43 is drawn; out. pressure is cut off from pipe I46 and pipe I40 is again out off from pressure and opened to discharge by-pass'pipe H53, while pipe I50 is opened to discharge. pipe and pressure is supplied to pipe I28 whereby piston I3 is forced to the left and shifts wedge II accordingly. Throttle valve 44 in pipe I26 regulates the rate of movement of wedge II in either direction. Tension valve MI is inserted in pipe I40 to maintain the fluid therein at proper: pressure depending upon the pressure conditions imposed. 1

With the support 'IG in adjusted position the press is readyfor operation 'under control of lever 3'2. Lever 3'! is'raised to eject the work pressed and to run out the table 25 for removal of the Work and placement of another piece, whereupon the lever is depressed to effect one pressing operation-which may be repeated if subsequent pressing operations with the'same or a different tool is desired-after which: movement again upward of lever 3'7 will-present'the pressed work for removal. The press table is automatically returned to position andthe op-' eration of the press is automatically limited to one stamping operation as will be explained while safety is assured by the several rod and recess provisions-as described in referenceto rods 3i and 32, and as will be described in reference to red I43 and recess I42. V a v When lever 31 is raised, fiuid pressure is-transmitted from pipe Ifldthrough pipe H (Ito maintain the coupling H12 disengaged; and through pipe'i59 to thecylinder II'I below-piston 28-to raise the ejector rod 21 and i the coacting member 26 in the shiftable press table} As the piston 28 nears the limit of its-stroke. valve portions 35 operate to admit fluid pressure to pipe JIS'I, from pipe I59, and thence behind piston 23': in cylinder 2% Which operates torun out the table 22 and plate25; the upper portion 23 0f the ejector being carried out of alignmentwith rod 21. 1 l When lever 31 was raised, member I23carriedoy the rod 39, was displaced so thatglatch member I34 engaged the recess I31 to hold lever 37. in raised position. As-the piston 23'-travelsin cylinder 24, it eventually uncovers pipe 133 by which pressure is conducted to cylinder I28 beneath piston. 539, which operatestto raise latch member I34 and release rod'39. A throttle valve 39 in pipe I38 delays the operationof pist'on I30 a time sufficient for removal of the work and placement of another piece.- Rod 39 then moves to middle positionunder the action-o'fspring I38, whereupon pressure is transmitted through pipeIEB to cylinder HT above piston 28 and at the same time to cylinder 24 to return pistons 28 and 23 respectively to their former positidrisi Table 22 and plate 25 follow pisto'n 23 and when the ejector portion 23' is again aligned with-portion 22 it drops into abutment with member 21. Pipe I48, uncovered by lower valve portion 35, communicates with discharge pipe 93 and releases the pressure from cylinder?! while -pipe I59, opened to discharge when rod 39 was' returned to middle position, releases the pressure below piston 28. r y 1" When lever 31 is depressed, as isin order fwhen the foregoingoperations have been completed;

.fluid pressure is transmitted from pipe I through pipe I58 to maintain the ejector rod depressed and the plate 25 in position, and through pipe II 4 to move shaft 33 to engage the coupling I02 and drive the toggle mechanism of the press. At the time lever 31 is depressed, member I 23 carried by rod 39 is displaced so that latch member !33 engages the recess I 3'! to hold rod 39 to the left.

The shaft 45 driving the toggle mechanism makes one complete revolution, effecting one pressing operation, whereupon lobe I53 on cam H9 depresses valve rod I54.. Fluid pressure from pipe I00, transmitted through pipe I52 and acting on valve piston I55 in cooperation with spring I55, is then transmitted through pipe I35 to cylinder I21 below piston I29 which operates to raise latch member I33 and allow rod 3%! to return to middle position under the action of spring I38. While shaft 45 is turning, pipe I33 is connected to discharge through pipe II which connects with pipe III.

If several tools are employed, these are selected in turn and lever 33 depressed for effecting the operation of each with respect to the Work piece, after which lever 31 is raised, the work ejected, and replaced when the table and plate are run out, as described. Where it is intended to use several tools, for example one punch each for the first, second and finishing operations, the three diiferent punches may be mounted on the tool carriage 40, Figs. 1-3, which can be moved manually for bringing the punches successively into their operating positions.

The press serves in particular for the forging of cartridge bottoms, or for the manufacture of forks, knives, and spoons, or generally, wherever three tools operate in sequence, the first tool roughing, the second finishing and the third sizing the work. The pressure under which the work is pressed, is high and the stroke of the ram is comparatively short. Instead of three tools, two tools, or one tool might be used. After the third or finishing tool has performed its operation, the handle or control lever 31 is raised, oil under pressure enters the pipe I59 and the operation already described is repeated.

The spring I38 operates between stops I62, I63, which are disposed in an enlarged portion I60a of the casing I60 and abut against opposite shoulder portions of smaller diameter. When rod 39 is moved to the right, member I23 engages stop I62 which moves to the right and compresses spring I38 against the stop I63, until latch I34 engages the notch I31. "When rod 39 is moved to the left, a head member I64, on rod 39 engages stop I63 which moves to the left and compresses spring I38 against the stop I62 until latch I33 engages notch I31. With rod 39 in either right or left operated position, therefore, spring I38 is compressed to restore the rod to middle position when the holding latch is raised. In order to ensure that the tool carriage is in the correct position when the press is operated, a recess I42 is provided in the carriage 40 and a lock member I43 is provided to engage said recess when the carriage is in its working position, thereby releasing the control members 31, 38 for the drive of the machine, through rods I44, I45.

The machine cannot be started when the tool slide or carriage 40 is not in the proper position, that is, the rest rod I43 does not engage in the opening I42. If it does so engage, the handle 31 can be thrown over since it is connected to the rest rod I43 through links I44 and, I45,

While we have herein shown and described certain preferred embodiments of our invention, we wish it to be understood that we do not confine ourselves to all the precise details herein set forth by way of illustration, as modification and variation may be made without departing from the spirit of the invention or exceeding the scope of the appended claims.

We claim:

1. In a toggle lever press, a ram, a motor for driving said ram, clutch means for coupling said motor to said ram; a hydraulic operating system comprising a source of hydraulic pressure, means for utilizing said pressure to operate said clutch means, a control valve selectively operative to apply pressure to the last said means for mechanically" driving said ram, said control valve having retaining means effective in the operated position of said valve, automatic releasing means connected with said ram and with said retaining means and. operative to release said retaining means when said ram has completed one cycle of operation in said press, whereby pressure is removed from said clutch means, a table for said press having work ejecting means; and actuat'mg means for said control valve having safety means operatively related to said work ejecting means and effective to prevent operation of said control valve when said work ejecting means is in operation.

2. In a toggle lever press, a table and Work ejecting means vertically operable through said table; a hydraulic operating system comprising a source of hydraulic pressure, means for utilizing said pressure to operate said work ejecting means with respect to said table, a control valve selectively operative to apply pressure to said means, said control valve having retaining means ell'ective. in the operated position of said valve, and automatic releasing means controlled by said work ejecting means and effective with respect to said retaining means to release said valve.

3. A toggle lever press as set forth in claim 2 wherein the table is movable and provided with means for utilizing hydraulic pressure to shift the table, and in which said work ejecting means is divided into an upper portion movable with said table and a lower actuated portion; and including valve means associated with said lower portion and with said means for utilizing hydraulic pressure to operate said work ejecting means, for applying pressure to the means for utilizing pressure to shift said table, when said work ejecting means has been operated; said automatic releasing means being also controlled by the table and operative to release said control valve when the table has substantially completed a predetermined movement, whereby both said pressure utilizing means are restored to inactive condition.

4. A toggle lever press according to claim 2 and further comprising means for shifting said table and ejecting means relative to said pressure utilizing means, a feeler for locking said utilizing means against operation, a second feeler for locking said table against horizontal shifting when said utilizing means is in engageable relationship to said ejecting means, and means jointly controlled by said feelers when in said. locked positions for permitting the operation of said valve.

ADOLF SCHNEIDER. EWALD UNGETHUEM. 

